Respiration apparatus



March 25, 1947. A. J. KIZAUR RESPIRATION APPARATUS Filed May 29, 1943 3 Sheets-Sheet 1 II T;

' IIIIIIIIIIIIII Invent or: Arthur J. Kizaur,

His Attorney March 25, 1947. K|ZAUR 2,418,034

RESPIRATION APPARATUS Filed May 29, 1943 3 Sheets-Sheet 2 Inventor: Arthur -J. Kizaur;

by MM ttorney.

March 25, 9 A. J. KIZAUR 2,418,034

RESPIRATION APPARATUS Filed lay 29, 1943 3 Sheets-Sheet 3 Inventor Arthur J. Kizaur;

b JV MMAM Hi Attorney Patented Mar. 25, 1947 RESPIRATION APPARATUS Arthur J. Kizaur, Cicero, Ill., assignor to General Electric X-Ray Corporation, Chicago, 111., a corporation of New York Application May 29, 1943, Serial No. 489,045

31 Claims. 1

My invention relates to respiration apparatus and particularly to a respiration device for supplying air, oxygen, anesthetic or other vapors or gases to a persons lungs.

For some time, there has existed a need for a respiration device which automatically functions either as a resuscitator or an inhalator depending upon the respiratory condition of the individual on whom the device is being used and particularly for a device of this character which is of such a lightweight construction that it can be easily and quickly transported from one place to another. Such a device has many uses. For example, it may be used to revive persons suffering from a respiratory failure resulting from gas poisoning, drowning, disease, nervous shock, and other causes, and to initiate respiration in. newborn babies. It also may be used to deliver anesthetic, oxygen or other vapors or gases to individuals for therapeutic purposes and during operations when the patients respiration is slow and shallow. It may also be employed to deliver oxygen to individuals who work in atmospheres containing poisonous gases, dust or a deficiency of oxygen. Such a device also would have great utility in connection with high altitude flying as there has long existed a need for a device which automatically supplies the necessary additional oxygen required for respiration purposes at very high altitudes and which, at the same time, can be easily and comfortably worn by the user. In fact, the lack of such a device has greatly restricted the development of flying at high altitudes.

One object of my invention is to provide an improved respiration device which is adapted to supply oxygen, anesthetic or other gas under positive pressure to a person's lungs during inhalation and to eifect the free exhaust of the gas from the lungs to the atmosphere during exhalation.

Another object of my invention is to provide an improved respiration device in which the inhalation phase of the respiratory cycle is effected by forcing the oxygen, anesthetic or other vapor or gas being used into the lungs until the lung pressure builds up to a predetermined maximum value above the atmospheric pressure, whereupon the exhalation phase of the respiratory cycle is effected by letting the gas in the lungs escape to the atmosphere until the gas pressure in the lungs decreases below a predetermined low value above the atmospheric pressure when the inhalation phase of the respiratory cycle is again effected.

A further object of my invention is to provide an improved arrangement of parts in a respiration device so that the pressure limits between which the gas pressure in the lungs is varied by the respiration device can be readily adjusted.

An additional object of my invention is to provide a respiration device which will automatically adapt itself to the users requirements so that as long as the user is breathing and has a respiratory rhythm of his. own the device operates as an inhalator and follows the users respiratory rhythm although the rate and depth of the users own respiration may fluctuate materially, but in case the user stops breathing, the device automatically operates as a resuscitator to produce artificial respiration at a predetermined rate until the user again starts to breathe naturally.

Another object of my invention is to provide a small, lightweight respiration device of the type that supplies gas under positive pressure to the users lungs during inhalation and permits the free exhaust of the gas from the lungs to the atmosphere during exhalation, which can be comfortably worn by the user and the operation of which is unafiected by vibrations or the position in which the device is held while being used.

Another object of my invention is to provide a respiration device in which the ratio of the inhalation period to the exhalation period of the respiratory cycle can be readily adjusted by the user, but after being so adjusted, the ratio is unaffected by any adjustments made in the: maximum or minimum pressure values maintained by the device.

A till further object of my invention is to provide an arrangement for effecting an increase in the rate at which the gas is supplied to the device when a negative pressure, namely a pressure below atmospheric pressure, is for any reason produced in the respiration device.

Another object of my invention is to provide an improved respiration device in which the gas used to operate the device is also used for respiratory purposes.

My invention will be better understood from the following description when taken in connection with the accompanying three sheets of drawings, and its scope will be pointed out in the appended claims.

In the accompanying drawings, Fig. 1 is a perspective view of a person wearing a respiration equipment embodying my invention; Fig. 2 is a. schematic diagram of a respiration device embodying my invention; Fig. 3 is a back elevation view, with certain of the parts broken away, of a practical embodiment of the respiration device schematically shown in Fig. 2; Fig. 4 is partly a sectional view on the line 4-4 of Fig. 3 in the direction indicated by the arrows and partly an elevation View looking in the same direction with the outer casing cut away along the line 4-4; Fig. 5 is partly a sectional view on the line 5--5 of Fig. 3 in the direction indicated by the arrows and partly an elevation view looking in the same direction with the outer casing cut away along the line 5-5; Fig. 6 is an enlarged perspective view of the pivot adjusting mechanism; Fig. 7 is an exploded View of the embodiment of myinvention shown in Figs. 3 to 6, inclusive, with some of the parts thereof shown in perspective and in section; Fig. 8 is a schematic diagram of a modification of the device shown in Figs. 2 to 7, inclusive; and Fig. 9 is an exploded view showing a modified portion of the respiration device shown in Figs. 3 to 7, inclusive.

This application is a continuationin-part of my copending application, Serial No, 474,798, filed February 5, 1943.

Referring first to Fig. l, I represents a cylinder containing gas, such as oxygen, under high pressure which is connected to a supply pipe 2 through a suitable adjustable pressure reducing valve 3 so that the gas pressure in the pipe 2 can be maintained at different predetermined constant values such, for example, as any value between one and a half and three and a half pounds per square inchabove the ambient atmospheric pressure. A respiration device 5, embodying my invention, is interconnected between the supply pipe 2 and one end of a flexible pipe or hose 6 the other end of which is attached to a suitable mask 1 so as to establish a gas connection between the tracheal passage of the person wearing the mask and the respiration device 5. The mask I is heldagainst the wearers head by a strap 8; the respiration device 5 is supported by a strap 9 around the wearers neck so that the device rests against the wearers chest; and the oxygen cylinder I is carried by a strap I around the wearers shoulder so that the entire respiratory equipment is easily and comfortably carried by the user. In many instances, however, it may be desirable to use an oxygen tankof sufficient capacity to supply oxygen continuously to the user for a long period of time; in Which case, the tank I may be too heavy to be carried about by the user. In such instances, the supply pipe 2 can be made long enough to allow the user to move about freely while the oxygen tank remains in a stationary position.

Furthermore, it will be'apparent that my in-' vention is not limited to any particular way of carrying the respiration device or to any particular way of establishing a gas connection between the device and the user's lungs.

Referring now to Fig. 2, which is a schematic" diagram of a respiration device 5 embodying my invention and adapted for use in a respiratory equipment of the type shown in Fig. 1, II represents a gaschamber which is arranged to be connected by the pipe 5 to the lane: of the user so that all of the gas flowing to and from the lungs through the pipe 6 passes through the chamber II. In order that the chamber II may be connected to the user's tracheal passage so that the gas pressures in the chamber and the users lungs are substantially the same, the pipe 6 is made as short as possible and has a relatively large cross section so that the pressure drop between the chamber II and the users lungs is substantially nil and the pressure in the chamber II follows changes in the lung pressure with substantially no time lag.

During inhalation, the chamber II is arranged to be supplied with gas from the supply pipe 2 through a gas conduit or passage I 2, and also through the series connected gas passages I3 and I4, but during exhalation, the gas in the chamber I I is arranged to be exhausted to the atmosphere only through the series connected gas passages I3 and I4. For effecting the flow of gas through the passages I2, I3 and I4, in this manner, I provide a combined inhalation and exhalation valve device I5 having two positions, in one of which agas connection is established between the supply pipe 2 and the passages I2 and I4 and in the other of which a gas connection is established between the passage I4 and the atmosphere. The valve device I5 comprises a diaphragm I6 which is connected between two hollow casings I! and I8 so that a gas chamber is formed by the interior of each of the casings and the'diaphragm. The gas chamber formed in thecasing IB is divided into two substantially equal-portions I9 and 20 by a partition 2| which projects inwardly far enough toward the diaphragm I6 from the closedend of the casing I8 to be engaged by the diaphragm. A spring 22' normally biases the diaphragm I6 away from engagement with the partition 2| of the casing I8 and into engagement with an inwardly projecting flange 23 which surrounds an opening whichi-is connected to the atmosphere by the holes 36 in the casing II. The gas chambers I9 and 2|] are respectively connected to the gas passages I2 and I4; andthe' supply pipe 2 is connected to a port 24 so located in the partition 2| that it is covered by the diaphragm I6 when it is in engagement with the partition 2|. The diaphragm I6 is also provided with an opening 25 which connects the gas chamber 20 with the gas chamber 26 in the casing II.

Therefore, when the diaphragm-I6 is in' the position to which it is normally biased by the spring 22 and which is the inhalation position of' the valve, gas is supplied from the supplypipe '2 through the port 24m both of the gas chambers I9 and 20 and fromthese chambers to sages I2 and I4, respectively. H

In a manner which will be hereinafter described, the diaphragm I6 is arranged to be moved against the bias of the spring 22, from its inhalation position to its exhalation position, in which position the opening to the atmosphere in the project on 23 is uncovered and the diaphragm I6 seats against the top of the trainsthe 'pasverse partition 2| so that the port 24 in the partition 2| is covered by the diaphragm. Therefore, when the diaphragm I6 is in its exhalationposition, communication is shut ofi between chambers I9 and 20 the gas connection between the supply pipe 2 and the chambers I9 and 20 is shut off and a gas connection is established between the gas passage. I4 and the atmosphere through the chamber 20, the opening 25 in the diaphragm I6, the chamber 26, the "opening in the projection 23 and the holes 36- so that the gas pressure in the passage I4 is free to exhaust to the atmosphere.

In a respiration device of the character to which my invention relates, it is desirable during 1 the inhalation period of the respiratory cycle to build up the gas pressure in the lungs to a predetermined positive value, namely a value above the ambient atmospheric pressure, then allow the gas pressure in the lungs to exhaust to the atmosphere until the lung pressure has decreased to a predetermined low positive value just above the ambient atmospheric pressure and then supply gas under pressure again to the lungs to start another respiratory cycle. I provide in such a device suitable means which will respond quickly both to the lung pressure reaching a predetermined maximum positive pressure and also to the lun pressure decreasing to a predetermined minimum positive value. Since the chamber I in the embodiment of my invention shown in Fig. 2, is so connected that the gas pressure therein is substantially equal to and follows with substantially no time lag the lung pressure, I use this gas pressure in the chamber II as a means for controlling the position of the diaphragm I6 of the valve device l5 to effect an inhalation and an exhalation at the proper time.

The means which I have shown for quickly responding to a predetermined maximum pres sure in the gas chamber includes a diaphragm 21, one side of which is exposed to the gas pressure in the chamber H and the other side of which is exposed to the ambient atmospheric pressure, and a movable member 28 which is in engagement with the diaphragm 21 so that the gas pressure in the chamber tends to move the member 28 in a predetermined direction. The movement in this predetermined direction, however, is opposed by two springs 29 and 30, one of which, such for example as spring 29, is adjustable. The movable member 28 also engages a diaphragm 3|, one side of which is exposed to the ambient atmospheric pressure and the other side of which is exposed to the gas pressure in a gas chamber 32, so that movement of the member 28 is also opposed by the gas pressure in the chamber 32. The gas chamber 32 is interposed between the gas passages l3 and I4 so that the flow of gas from either of these passages to the other is through the chamber.

The gas chambers H and 32 and the member 28 are so arranged that a simultaneous change in the gas pressures in both of the gas chambers effects a greater change in the moment produced by the gas pressure in the chamber II on the member 28 than in the opposing moment produced therein by the gas pressure in the chamber 32. This result is accomplished in my improved respiration device preferably by making the efiective areas of the diaphragm 21 and 3|, which are respectively exposed to atmosphere and to the pressures in the chambers H and 32, equal and by making the movable member 28 a pivoted member with its fulcrum 33 located at a point between the midpoint of the member 28 and the point where the member 28 engages the diaphragm 3| so that as the gas pressure in both of the chambers is simultaneously increased, the resultant moment produced on the pivoted member by the gas pressures in the two chambers increases and is in the opposite direction to the moments produced therein by the springs 29 and 30. Therefore, when the gas pressure in the gas chambers II and 32, is below a predetermined value the springs 29 and 30 maintain the movable member 28 in its normal position, but when the gas pressure exceeds this predetermined value, the pivoted member 28 is quickly moved to its other position. For changing the value of the gas pressure in the chambers II and 32 at which the movable membe 28 moves from its 6. normal position to its actuated position, I provide a rack 34 and pinion 35 for moving the fulcrum 33 to difierent points along the member 28 so as to vary the relative distances be- 5 tween the fulcrum 33 and the two ends of the member 28.

In response to the movement of the member 28 to its actuated position by the pressure in the chamber exceedinga predetermined Value the diaphragm l6 of the control valve l5 immediately moves from its normal inhalation position to its exhalation position and thereafter remains in its exhalation position until the pressure in the gas chamber decreases to a predetermined positive value slightly above the ambient atmospheric pressure.

For moving the valve l5 from its normal inhalation position to its exhalation position, I provide a gas engine which comprises 9, diaphragm 31 held between the open end of the casing I! and a casing 38 which is closed at the opposite end from the diaphragm 31 so as to form a gas chamber 40. Since the open end of the casing I1 is connected to the atmosphere through the holes 36, one side of the diaphragm I6 is exposed to the gas pressure in the chamber 40 and the other side is exposed to the ambient atmospheric pressure. The diaphragms 3! and H; are interconnected so that when the pressure in the chamber 40 reaches a value which is sufllcient to overcome the bias of the spring 22, the diaphragm I6 is moved from its inhalation position to its exhalation position. The chamber 40 is connected by a restricted passage 4| to the supply pipe 2, and also by a larger passage 42 to the gas chamber 32. The passage 42 terminates in the gas chamber 32 at a point near the diaphragm 3|, so that when the movable member 28 moves to its actuated position in response to the pressure in the chamber exceeding a predetermined value the diaphragm 3| shuts ofi the gas connection between the passage 42 and the chamber 32.

Since the passage 42 is larger than the restricted passage 4|, pressure cannot build up in the chamber 40 until the diaphragm 3| shuts ofi the passage 42. When, however, the passage 42 is shut off the pressure in the chamber 40 builds up quickly to the pressure of the gas in the supply pipe 2 and effects the quick movement of the diaphragm l6 of the valve device I5 from its inhalation position to its exhalation position, in which position the passage I4 is connected to the atmosphere through the opening 25 in the diaphragm IS, the opening in the projection 23 and the holes 36 to efiect a quick reduction of the gas pressure in the chamber 32 to the atmospheric pressure.

In accordance with one feature of my invention, the effective cross-sectional areas of the 0 "passage 4 and the opening 25 in the diaphragm l3 and the projection 23 are made much larger than the effective cross-sectional areas of the passage |3 which interconnects the two chambers and 32 so that when the valve device I5 moves to its exhalation position the gas pressure in the chamber 32 is quickly reduced to the ambient atmospheric pressure, but the gas pressure in the chamber II is reduced at a slower rate dependent upon the effective cross-sectional area of the passage l3. Therefore, when the valve l5 moves to its exhalation position, the moment of the gas pressure in the chamber 32 on the pivoted member 28 quickly decreases to zero so that the only moments then tending to restore the pivoted member 28 to its normal position are those produced by the springs 29 and 30. Consequently, in order to-efiect a return movement of the pivoted member 28 to its normal position, the gas pressure in the chamber II has to decrease to a lower value than the value which efiected the movement of the pivoted member 28 to its actuated position. The lower gas pressure in the chamber I I, at which the moments of the springs 29 and 30 overcome the moment of the gas pressure in the chamber II, can be readily varied by changing the tension of the spring 29. i

When the pivoted lever 28 is restored to its normal position in response to the gas pressure in the gas chamber II decreasing below a predetermined value above the atmospheric pressureduring an exhalation, the passage 42 is again un covered so that the gas pressure in the gas chamber 40 quickly decreases to a value which allows the spring 22 to move the diaphragm I6 to its inhalator position to effect another inhalation.

In order to prevent a sudden deep inhalation by the user of the apparatus from effecting a decrease in the pressure in the gas chamber II to a negative value, namely a pressure below the ambient atmospheric pressure, I provide means for increasing the rate at which the gas is supplied from the supply pipe 2 to the chamber II when the pressure in the chamber II decreases below the atmospheric pressure; This means comprises a gas passage 44 between the chamber II and the supply pipe 2 and a pivoted valve 45 which is normally biased to its closed position by a spring 46 so. as to shut off the gas connection between the passage 44 and the chamber I I. The valve 45 is so located in the chamber I I that it is opened by the movement of the diaphragm 21 into the chamber II in response to the atmospheric pressure exceeding the pressure in the chamber. Normally, with the gas pressure in the chamber II equal to or greater than the atmospheric pressure, the force exerted by the spring 46 is sufiicient to hold the valve 45 closed against the liftingaforce of the gas pressure in the passage 44 and any other force that may be tending to move the diaphragm 2'! into the chamber II.

The normal respiratory rate of a healthy adult at sea level is about fifteen to eighteen respirations per minute, and the ratio of the length of the inhalation period to that of the exhalation period is about one to two.

In order that my respiration device may have a similar respiration rate, the effective cross-sectionalzareas of the gas passages are so designed that when the device is being used at a predetermined altitude by an individual havinga normal lung capacity, an operating gas pressure in the supply pipe 2 of approximately 2 pounds above the ambient atmospheric pressure causes gas to flow into the chambers II and 32 and the users lungs at such a rate during theinhalation period of the device, as to build up the gas pressure therein to the desired maximum pressure in about the same time as the inhalation period of a normal respiratory cycle and to flow out of the cham-' hers I I and 32 and the users'lungs at such a rate during the exhalation period as to decrease the pressure therein to the desired minimum value in about the same time as the exhalation period of a normal respiratory cycle. In the particular embodiment, shown in Fig. 2, the desired ratio of the inhalation period to the exhalation period of about one to two is obtained by making the effective cross-sectional areas of the passages I2 and I3 substantially equal since the gas flows through both of these passages in parallel'during inhalation and only through the passage I3 during exhalation.

If the respiration device were to be used always at substantially the same altitude, there probably would be little need of providing means for ad'- justing the ratio of the inhalation period to the exhalation period of the device because any desired change in the frequency or rhythm of the device and in the volume of gas supplied to the chambers and the passages of the device and the users lungs during the inhalation period could' be effected without materially changing the ratio of the inhalation period to the exhalation'period merely by varying the pressure maintained inthe.

supply pipe 2 and by varying the position of the adjustable fulcrum 33.

Actual tests of my improved respiration device in atmospheric pressures existing at very high altitudes, however, have demonstrated that an arrangement of the passages I2 and I3 which produces a satisfactory operation at low altitudes results in such a rapid respiratory rhythm at very high altitudes as to produce an effect known as hyperventilation, namely, such a rapid rate of removal of the gas from the lungs that the carbon dioxide content is reduced to a sufficiently low value to afiect seriously the functioningofv the users respiratory center as well as his physical condition. This increase in the respiratory rhythm of the device at high altitudes is due to the fact that the density of the gas supplied to the device and the users lungs from the supply pipe 2 decreases as the ambient atmospheric Consequently, since the velocity at which gas flows through an orifice de-- creases with the density of the gas, the time it takes the volume of gas, necessarytofill the; device 5 and the users lungs to flow through the pressure decreases.

passages I2 and I3 decreases with the altitude In order that the respiratory rhythm of my improved device may be reduced at these hightion period of my device effected by the change,

in the density of the gas as the atmospheric pressure decreases produces no uncomfortable physiological effects, the means which I employ for varying the ratio of the inhalation period to the exhalation period is arranged to vary the effective area of the passage that exhausts the gas pres-,;

sure in the chamber II to the atmosphere without changing the total eifective area of the pas-' sages through which the gas is supplied to the chamber during inhalation. embodiment of my invention shown in Fig. 2 in which the passage I3 through which the gas in: the chamber II is exhausted to the atmosphereis also used to supply gas to the chamber I I during the inhalation period, I provide in the chamber II a reciprocallymovable valve 48 that is'so arranged that movement thereof in one direction simultaneously increases the effective area ofthe passage I2 and decreasesthe effective area of thepassage I3 the same amount and movement in the.

opposite direction simultaneously decreases the effective area of the passage I2 and increases the eiTective area of the passage I3 the same amount.

Therefore, movement of the valve 48 effects a change in the effective area of the exhaust pas- In the particular sage between the chamber II and the atmosphere without eifec-ting any change in the effective area of the passages supplying gas to the chamber I I during the inhalation period. The position of the valve 48 may be manually controlled by the user of the respiration device or it may be automatically adjusted by any suitable means.

The operation of the respiration device shown in Fig. 2 is as follows: The supply pipe 2 is connected to a suitable source of gas so that the gas pressure in the pipe is maintained at a predetermined low pressure above the ambient atmospheric pressure, and the pipe 6 is connected to the users tracheal passage by any suitable means such as a mask. The pressure of the gas in the supply pipe 2 and the positions of the fulcrum 33 and the valve 48 are then adjusted so that the device has a predetermined rhythm and the users lungs are filled with the proper amount of gas during th inhalation period.

If the user has no respiratory rhythm of his own, the device functions as a resuscitator having a rhythm dependent upon the position of the adjustable valve 48. When the control valve I5 is in its inhalation position so that the gas chambers I9 and 20 are connected to the supply pipe 2, gas flows from the chamber 20 through the passage I4 to the gas chamber 32 and from the gas chamber I9 through the gas passage I 2 to the gas chamber II. Gas also flows from the pipe 2 through the restricted passage 4|, the chamber 40 and the passage 42 to the gas chamber 32 and from the chamber 32 through the passage I3 to the gas chamber I I. Due to the passage 42 being larger than the restricted passage 4I, the pressure in the chamber 40 does not build up to a sufiicient value to cause the diaphragm 31 to move the diaphragm IE to its exhalation position. From the gas chamber II gas flows to the users respiratory organs through the pipe 6 until the gas pressure in the users lungs and in the chamber II builds up to a sufficient value to move the pivoted lever 28 to its actuated position. The diaphragm 3| then shuts off the gas connection between the passage 42 and the chamber 32 so that the gas pressure in the gas chamber 40 quickly builds up to a sufficient value to cause the diaphragm 31 to move the diaphragm IE to its exhalation position; in which position the gas connection between the supply pipe 2 and the passages I2 and I4 is shut off, and the gas connection between the pipe I4 and the atmosphere is established to allow the gas pressure in the chamber 32 to be reduced quickly to the atmospheric pressure. The gas chamber II is also connected to the atmosphere through the passage I3 and the chamber 32, but due to the relatively small cross-sectional area of the passage I3 an appreciable time elapses before the gas pressure in the chamber II decreases to a sufliciently low value to allow the springs ,29 and 30 to restore the lever 28 to its normal position.

v When the lever 28 is restored to its normal posisettings of the valve 48 the adjustable fulcrum 33 and the spring 29 as long as the user has no respiratory rhythm of his own.

If while the device is in operation the user has a respiratory rhythm of his own, the device functions as an inhalator and automatically synchronizes itself with the users respiratory rhythm. For example, assume that while the device is functioning to produce an inhalation, the user attempts to exhale. The result of such an action on the part of the user immediately increases the gas pressure in the chamber I I to a sufficient value to cause the pivoted member 28 immediately to move to its actuated position and, therefore, cause the device to produce an exhalation. Similarly, if the user attempts to inhale while the device is functioning to produce an exhalation, the reduction in the pressure in the chamber II effected by the attempted inhalation by the user causes the pivoted member 28 immediately to move to its normal position and start the device into operation to produce an inhalation.

While in use, the length of the inhalation period of each respiratory cycle of the device can be changed relative to the length of the exhalation period thereof by merely changing the position of the valve 48. If it is desired to increase the length of the exhalation period to prevent hyperventilation at high altitudes, the valve 48 is moved so as to cover more of the passage I3, and to uncover more of the passage I2 whereas if it is desired to decrease the length of the exhalation period, as is the case when the user descends from a high altitude to a low altitude, the valve 48 is moved so as to uncover more of the passage I3 and to cover more of the passage I2.

If the user takes a sufiiciently deep inhalation to reduce the gas pressure in the chamber II below atmospheric pressure, the diaphragm 21 is immediately moved into the chamber II by the atmospheric pressure so as to open the valve 45. A gas connection is then established between the passage 44 and the chamber II so as to increase the rate of flow of gas into the chamber II until the gas pressure therein is restored to the atmospheric pressure, whereupon the diaphragm 21 is restored to its normal position and valve 45 is closed by the spring 46.

In Figs. 3 to 7, inclusive, I have illustrated a practical embodiment of the respiration device schematically shown in Fig. 2, and in these figures, corresponding parts are designated by the same characters as in Fig. 2 wherever it has been convenient to do so.

The respiration device shown in Figs. .3 to 7, inclusive, comprises three main units; namely, a front unit containing the gas chambers and most of the gas passages of the device, a second unit fastened to the back of the front unit and containing the chamber pressure responsive mechanism, and a third unit which is also fastened to the back of the first unit and which contains the control valve and its operating mechanism.

The front unit comprises a block of suitable material containing two relatively large cylindrical holes, respectively constituting the gas chambers II and 32, and two substantially semicylindrical holes respectively constituting the gas chambers I9 and 20 which extend inwardly from the rear face of the block. The gas chambers II and 32 are located near each other in the top portion ofthe block 55, and the two semicylinbelow the chambers I I and 32 and with their longitudinal plane surfaces adjacent to each other. The gas passage I2, which interconnects the gas chambers I I and I9, consists of a hole through the partition which separates these two chambers. Similarly, the gas passage I3, which interconnects the gas chambers II and 32, consists of a. hole through the partition which separates them, and the much larger gas passage I4, which interconnects the gas chambers 26 and 32, also consists of a hole through the partition which separates these two chambers.

The gas is supplied to the device through the pipe 2 which extends into the bottom portion of the block 55 and which is connected by a gas passage 56 to a port 51 located in the back face of the block 55 in the partition 2| between the chambers I9 and 26. The supply pipe 2 is also connected to a port 58 in the front end of the chamber II by the gas passage 44 which is located in the front portion of the block 55 and also is connected to a port 59 located in the back face of the block 55 below the gas chambers I9 and 26, by the gas passage M. The gas passage 42, which is also located in the front portion of the block 55, interconnects a port 68 in the back face of the block 55 below the gas chambers I9 and 20 with a port GI centrally located in the front end ofthe chamber 32 and surrounded by a hollow cylindrical boss 62 that projects into the chamber 32. The biasing spring 30 surrounds the boss 62 and a cylindrical plug 63, having a restricted opening 64 therein, is held in any suitable manner in the cylindrical opening in the boss 62.

The port 58 in the front end of the chamber II is surrounded by a hollow cylindrical boss 65 which projects a short distance into the chamber I I, and is arranged to be covered by the valve 45 carried on one end of a lever 66 which is pivotally mounted on a bracket 61 secured to the block 55 at the front end of the chamber I l. The torsion spring 46, the ends of which respectively engage the lever 66 and the block 55, biases the lever 66 in a direction to maintain the valve 45 in engagement with the end of the boss 65 so as to shut off the gas connection between the chamber II and the port 58. The free end 69 of the lever 66 extends through the axis of the cylindrical chamber II for a purpose which will be hereinafter pointed out. An opening I6 extends through the block 55 from the front end of the chamber II and mounted therein in any suitable manner is a socket II of a connecting device for attaching the outlet pipe or hose 6 to the device.

The valve 48 which controls the relative effective cross-sectional areas of the gas passages I2 and I3 is mounted inside the cylindrical chamber I I for limited rotation about the axis thereof. The valve 48 is provided with an arcuated surface I2 which has the same radius of curvature as the chamber I I and which is held in engagement with the curved surface of the block 55 by a torsion spring 13, one end of which engages the valve 48 and the other end of which engages a screw !4 in the block 55. In order to prevent movement of the valve 48 toward either the front or the back end of the chamber I I, the width of the valve is made slightly smaller than the depth of the chamber II. and the diameter of the chamber I I near the back face of the block 55 is made slightly smaller than the diameter of the rest of the chamber so as to form, for the valve 48 to slide in, a shallow groove BI (see Fig. 4) having the same width as the valve 48. The openings from the passages I2 and I3 to the cham-- ber II are identical in shape and size, and the length of the arcuated surface I2 of the valve 49 is equal to the circumferential distance of the chamber II between the centers of these two openings so that any movement of the valve 48 over these openings differentially changes .the

effective cross-sectional areas of the passages I2 and I3 the same amount.

The valve 48 carries an arcuated rack 15 which is engaged by a pinion I6 secured to a rotatable shaft I7 that projects through the front of the block 55 and to which is secured a suitable knob 18 whereby the position of the valve 48 may be adjusted by turning the knob I8. The front surface of the block 55 is provided with a cylindrical boss I9 through which the shaft I'I passes. able packing is provided around the shaft 11 so as to prevent the gas in the chamber II from leaking to the atmosphere along the shaft 11.

A flanged collar 83 (see Figs. 4 and '7) is at-' tached to the boss 19 by a setscrew 84 and has secured thereto a fiat plate 85 which is located back of the knob I8 and contains a series of holes 86 arranged in a circle so that as the knob 18 isrotated, a spring pressed ball 81 carried by the knob is moved from one hole 86 to the'next.

Therefore, in order to change the setting of the l valve 48, sufiicient force has to be applied to the gaging a pin 88 (see Fig. 7) which is secured to the block 55 and which projects into the groove BI at a point near the edge of the passage I3 so that it is engaged by the valve 48 when the passage I3 is covered a predetermined amount by Similarly, the movement of the valve 48 in the opposite direction is limited by the valve the valve.

engaging a pin 89 which is secured to the block 55 and which projects into the groove 8| at a point near the edge of the passage I2 so that it is engaged by the valve 48 when the passage I2 is covered a predetermined amount by the valve.

The chamber pressure responsive unit comprises a hollow housing or casing 90 which is ar ranged to be attached by the screws- 9I to the back of the block 55 so that it encloses the back ends of the chambers II and 32. The rear' side 93 of the casing 90 is preferably attached thereto by the screws 95 so as to provide easy access to the interior of the casing. The front side of the. casing 90 contains two round holes respectively having the same diameter as the chambers I Land 32 and in alignment therewith when the casing. 90 is attached to the block 55. A strip of suitable material 94 is cemented or otherwise securedto the front face of the casing 90 so that it is between the casing 90 and the block 55 when they are attached to each other and serves as a gasket between the adjacent faces thereof and also as the diaphragms 21 and 3I of the pressure responsive mechanism.

A small, round, thin plate 96 is centrally cemented or otherwise secured to the chamber side of the diaphragm 21 and is provided at the center thereof with a small knob which projects into the chamber II so that the knob depresses the arm 69 of the pivoted lever 66 of the front unit against the opposing bias of the spring 46 when the gas pressure in the chamber II decreases below atmospheric pressure.

Suit- A small thin disk 98 is also centrally cemented or otherwise secured to the chamber side of the diaphragm 3I (see Fig. 4) and is arranged to engage the rear end of the cylindrical plug 63 so as to cover the opening 64 therein when the diaphragm 3| is moved into the gas chamber 32 in response to the gas pressure in the gas chamber II exceeding a predetermined maximum value. One end of the coil spring 30, which surrounds the boss 62 on the front unit, bears against the disk 98 so as to oppose the movement of the diaphragm 3| into the chamber 32.

A large round flat plate 99 is centrally cemented or otherwise secured to the outer side of the diaphragm 21 and is provided on opposite sides of the center thereof with small outwardly projecting lugs I which are pivotally connected to one end of the lever 28, the other end of which is pivotally connected to similar lugs I0l of a large round fiat plate I02 which is centrally cemented or otherwise secured to the outer side of the diaphragm 3 I.

The center portion of the lever 28 is constructed so that it forms a loop within which a block I03 is mounted for movement lengthwise of the lever 28 by providing the block I03 with a plurality of straight rods I04 which project from opposite sides of the block in directions parallel to the line connecting the centers of the diaphragms 21 and 3| and which are slidably mounted in the lever 28 on opposite sides of the loop. This construction allows movement of the block I03 and th rods I04 lengthwise of the lever 28 but allows no relative rotary movement between the block I03 and the lever 28. The block I03 is rotatably mounted on a cylindrical pin I05 located between the lever 28 and the front side of the casing 90 and with its axis at right angles to the plane of movement of the lever 28 so that the pin I05 serves as the fulcrum about which the lever 28 and the block I03 rotate as a unit. The pin I05 is rigidly secured to a plate I06, the upper end of which is provided with a plurality of straight rods I01 which project from opposite sides of the plate in directions parallel to the rods I04 and which are slidably mounted in a bracket I08 fastened to the back of the front side of the casing 90 by the screw I09. The lower end of the plate I06 is slidably mounted in a groove IIO formed in a bracket I I I which is fastened to the back of the front side of the casing 90 by the screw I I2. The groove II!) is also parallel to the rods I04 and I01 so that the movement of the pin I05 and the plate I06 is limited to a rectilinear movement in a direction parallel to the rods I04. The plate I06 also is provided with the rack 34 which is engaged by the pinion 35 secured to a rotatable shaft II3 that extends through the hole H4 in the block 55 to the front of the device where a knob I I5, preferably of the same construction as the knob 18, is fastened to the shaft H3 so that the position of the fulcrum pin I05 may be adjusted relatively to the ends of the lever 28 by manually turning the knob I I5.

The adjustable spring 29 is connected between a projection II1 of the lever 28 and an arm II8 attached to the bracket III by the attaching screw I I2 so that a force is exerted by the spring 29 in a direction to rotate the lever 28 toward the diaphragm 21.

In order to prevent the block I03 and the lever 28 from moving lengthwise along the pin I05, the block I03 extends through an opening I in the plate I06 so that the top and bottom surfaces of the block I03 respectively engage the top and bottom surfaces of the opening I20. The opening I20, however, is made wide enough to allow free rotation of the block I03 about the pin I05. A link I 23 which is pivotally connected to the projection II1 of the lever 28 and to the stationary arm I I8 serves to prevent the lever 28 from being moved lengthwise and thereby changing the forces exerted on the diaphragms 21 and 3|. The pivotal connection between the link I23 and the projection H1 is located in the plane of movement of the axis of the adjustable pin I05 and so designed that the very limited relative movement between the link and the projection which occurs when the lever 28 moves between its inhalation and exhalation positions does not produce any binding between the block I03 and the rods I04.

A hole I2I is provided in the casing so that the pressure in the interior of the casing is always the atmospheric pressure. The casing 90 also has attached thereto one or more buttons |l22 whereby a supporting or carrying strap may be attached to the device.

The control valve unit of the device shown in Figs. 3 to '1, inclusive, comprises a casing having a main hollow portion 39 and a rear cover portion 38 which are held together by a plurality of screws I25 with the diaphragm 31 between them. The screws I25 also fasten the casing 39 to the back of the block 55 with the diaphragm I6 between the casing 39 and the lower portion of the back face of the block 55 which contains the ports 51, 59 and 60 and the openings into the chambers I9 and 20.

The front face of the casing 39 is so constructed that when the valve unit is attached to the back of the block 55, the circular portion of the diaphragm I6 which covers the port 51 and the rear end of the gas chambers I9 and 20 is movable relative to the back face of the block 5 5. A thin disk I26 of suitable material is centrally secured to the rear side of the circular portion. of diaphragm I6 and is provided with a pin I21 which projects through the center of the diaphragm I6 and into the opening 51 where it engages one end of the coil spring 22, the other end of which bears against the block 55. The force exerted by the spring 22 normally is sufilcient to hold the diaphragm I6 away from the port 51 and to maintain the rear side of the disk I26, which preferably has secured thereto another disk I28 of suitable elastic or flexible material, against the forward extending annular flange 23 which surrounds the circular opening I29 in a partition I30 that divides the cylindrical opening in the casing 39 into the front section or chamber I9 and a rear section which is connected to atmosphere through the openings 36 in the sides of the casing 39. The diaphragm I6 contains the opening 25 which is located behind the gas chamber 20 so that a gas connection is established at all times between the gas chamber 20 and the front gas chamber 26 in the casing 39.

The diaphragm 31 completel covers the rear side of the casing 39, and a disk I33 is secured to the front side thereof and is provided with a pin I34 which extends through the opening I29 and engages the disk I20 on the diaphragm I6 so that forward movement of the diaphragm 31 causes the diaphragm I6 to be moved forward against the bias of the spring 22.

The rear cover portion 38 of the casing is provided with a cylindrical opening constituting the gas chamber 40 which is connected to the gas passages 4| and 42 in the front block 55 of the aaraoes device by means of the holes I36 and I31 which extend through the diaphragms I6 and 31 and the casing 39 and which are respectively in alignment with the ports 59 and 60 in the rear face of the block 55 and with the ports I36 and I39 in the front face of the cover plate 38. These ports I38 and I39 are respectively connected by the gas passages I40 and MI to the gas chamber 40. The hole I36 in the casing 39 contains a restricted plug I42, the opening of which is smaller than the opening 64 in the plug 63 so that the effective cross-sectional area of the gas connection from the supply pipe 2 through the passage 4|, the hole I36 and the passage I40 to the gas chamber 40 is smaller than the effective crosssectional area of the gas connection from the gas chamber 40 through the gas passage I4I, the holes I31 and the gas passage 42 to the gas chamber 32.

Since the operation of the embodiment shown in Figs. 3 to '1, inclusive, is thesame as the embodiment schematically shown in Fig. 2, a description thereof is believed to be unnecessary.

In Fig. 8, I have schematically illustrated a modification of the embodiment of my invention shown in Figs. 2 to 7, inclusive, in which the diaphragm I6 of the control valve I5 is actuated by an electromagnet instead of by a gas engine. The diaphragm I6 is normally biased to its exhalation position by a spring I50 and is arranged to be moved to its inhalation position by an electromagnet I52, the plunger armature I53 of which is fastened to the diaphragm I6. The winding I54 of electromagnet I52 is connected in an electric circuit which includes a suitable source of current I55, a contact I56 carried by the pivoted lever 28 and arranged to be moved into engagement with a stationary contact I51 when the pivoted lever 28 is in its normal position and the contacts I58 of a manually controlled switch which is closed when the respiration device is in use. Therefore, when the device is in use, the movement of the pivoted lever 28 to its normal position in response to the pressure in the gas chamber II decreasing below a predetermined value moves the contact I56 into engagement with the contact I51 so as to complete an energizing circuit for the winding I54 of the electromagnet I52 to effect the movement of the diaphragm I6 to its inhalation position, and the movement of the pivoted lever 28 to its actuated position in response to the pressure in the gas chamber II increasin above a predetermined value moves the contact I56-out .of engagement with the contact I51 so that the electromagnet I52 is deenergized to allow the spring I50 to move the diaphragm I6 to its exhalation position.

In Fig. 9, I have shown a modification of the respiration device shown in Figs. 3 to '7, inclusive, in which the control valve is operated by an elec'tromagnet. The front unit of the respiration device shown in Fig. 9 is the same as the corresponding unit of the device shown in Figs. 3 to 7, inclusive, except that the gas connection "from the gas chamber 32 to the port 60 and the gas connection from the supply pipe to the port 59 are omitted. The gas chamber pressure responsive unit in Fig. 9 is also the same as the corresponding unit shown in Figs. 3 to '1, inclusive, except that the pivoted lever 28 carries-the contact I56 which engages the stationary contact I51 when the lever is in its normal or inhalation position. The contact I56 is connected by means of a flexible lead I63 to a stationary terminal I64 secured to and extending through the casing 90.

16 The stationary contact I51 is connected to another terminal I65 secured to and extending through the casing 90. Also, in order to prevent any arcing at the contacts I56 and I51 inside the casing from igniting any inflammable gases the atmosphere outside the casing, the opening I2I which connects the interior of the casing, 90

to the outside atmosphere contains a tubular screen I66 of fine wire gauz which projects into the interior of the casing 90 and completely encloses the opening I2 I.

In the control valve unit of the device shown in Fig. 9, the diaphragm 31 and the cover portion 38 of the device shown in Figs. 3 to '1, inclusive, are replaced by the electromagnet I52, the winding I54 of which is wound on a spool I61, one end of which is secured to the inner side of the end cover of a cylindrical housing I68. This cylindrical housing extends into the central circular opening I29 in the casing 39 and is provided with the side brackets I69 that are attached to the rear side of the casing 39 by the screws I10. The electromagnet I52 is provided with the plunger armature I53, one end of which is connected to the center of the diaphragm I6 by a screw HI and the other end of which engages one end. of the coil spring I50. The other end of the spring I50 bears against the closed end of the housing I68 so that the plunger I53-is normally biased toward the front of the device and the diaphragm I6 is held in its exhalation position. When, however, the plunger I53 is attracted into the electromagnet by the winding I 54 thereof being energized, the movement of the plunger to its attracted position moves the diaphragm I6 to its inhalation position.

While I have, in accordance with the Patent Statutes, shown and described several embodiments of my invention, changes and modifications will be obvious to those skilled inthe art, and I therefore aim in'the appended claim fto cover all such changes and modifications as fall within the true spirit and scopeof my invention.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. A valve device for controlling the -flow of gas between a source of gas under pressure and a tracheal passage and between the tracheal passage and the atmosphere comprising gas pressure conducting means, a gas chamber having an opening through which passes the gas flowing between said chamber and the tracheal passage, said opening being of suihcient cross section not to prevent the pressure in said chamber from immediately following changes in the tracheal passage, a pressure responsive device responsive to the gas pressure in said chamber and having a movable member which moves quicklyffrom one predetermined position to a second predetermined position in response to said gas pressure increasing above a predetermined ,value above the atmospheric pressure and which moves back quickly fromsaid second predetermined position to said one predetermined position in response to said gas pressure decreasing below a predetermined value below said first mentioned value but above the atmospheric pressure, and means controlled by the position of said member for selectively establishing gas connections between said chamber and said gas pressure conducting means and between said chamber and the atmosphere.

2. A valve device for controlling the flow of gas between a source of gas under pressure and a tracheal passage and between the tracheal passage and the atmosphere comprising gas pressure conducting means, a gas chamber having an opening through which passes the gas flowing between said chamber and the tracheal passage, said opening being of sufilcient cross section not to prevent the pressure in said chamber from immediately following changes in the tracheal passage, a pressure responsive device responsive to the gas pressure in said chamber and having a movable member which moves quickly from one predetermined position to a second predetermined position in response to said gas pressure increasing above a predetermined value above the atmospheric pressure and which moves back quickly from said second predetermined position to said one predetermined position in response to said gas pressure decreasing below a predetermined value below said first mentioned value but above the atmospheric pressure, and means controlled by said pressure responsive device for establishing between said gas pressure conducting means and said chamber a gas connection having a predetermined effective cross sectional area when said movable member is in said one predetermined position and for shutting off said gas connection between said chamber and said gas pressure conducting means and for establishing between said chamber and the atmosphere a gas connection having a smaller predetermined effective cross sectional area than said first mentioned gas connection when said movable member is in said second predetermined position. a

3. A valve device for controlling the flow of gas between a source of gas under pressure and a tracheal passage and between the tracheal passage and the atmosphere comprising gas pressure conducting means, a gas chamber having an opening through which passes all the gas flowing between said chamber and the tracheal passage, and means controlled by the gas pressure in said chamber for selectively establishing gas connections between said gas pressure conducting means and said chamber and between said chamber and the atmosphere.

4. A valve device for controlling the flow of gas between a source of gas under pressure and a tracheal passage and between the tracheal passage and the atmosphere comprising gas pressure conducting means, a gas chamber having an opening through which passes all the gas flowing between said chamber and the tracheal passage, means for establishing between said gas pressure conducting means and said chamber a gas connection having a predetermined effective cross sectional area, means responsive to the gas pressure in said chamber exceeding a predetermined value above the atmospheric pressure for shutting off said gas connection between said gas pressure conducting means and said chamber and for establishing between said chamber and the atmosphere a gas connection having a smaller predetermined efiective cross sectional area than said first mentioned gas connection, and means responsive to the gas pressure in said chamber decreasing below a predetermined value above the atmospheric pressure for shutting ofl said gas connection between said chamber and the atmosphere and for reestablishing said gas connection between said chamber and said gas pressure conducting means.

5. A valve device for controlling the flow of gas between a source of gas under pressure and a tracheal passage and between the tracheal passage and the atmosphere comprising gas pressure conducting means, a gas chamber having an opening through which passes the gas flowing between said chamber and the tracheal passage, a plurality of gas passages connected to said chamber, means for establishing a gas connection between said plurality of gas passages and said gas pressure conducting means so that gas is supplied in parallel through said passages to said chamber, means responsive to the gas pressure in said chamber exceeding a predetermined value above the atmospheric pressure for shutting ofi said gas connection between said gas pressure conducting means and said plurality of gas passages and for establishing a gas connection between a portion of said plurality of gas passages and the atmosphere, and means responsive to the gas pressure in said chamber decreasing below a predetermined value above the atmospheric pressure for shutting off said gas connection to the atmosphere and for reestablishing said gas connection between said plurality of gas passages and said gas pressure conducting means.

6. A valve device for controlling the flow of gas between a source of gas under pressure and a tracheal passage and between the tracheal passage and the atmosphere comprising gas pressure conducting means, a gas chamber having an opening through which passes the gas flowing between said chamber and the tracheal passage, a movable member, actuating means for said member operated by the gas pressure in said chamber for quickly actuating said member from one predetermined position to a second predetermined position in response to said gas pressure exceeding a predetermined value above the atmospheric pressure and for quickly actuating said member from said second predetermined position to said one predetermined position in response to said gas pressure decreasing below a predetermined lower value above the atmospheric pressure, and means responsive to the actuation of said member to said second predetermined position for establishing a gas connection between said chamber and the atmosphere and for shutting off the gas connection between said gas pressure conducting means and said chamber and responsive to the actuation of said member to said one predetermined position for establishing a gas connection between said chamber and said gas pressure conducting means and for shutting oit said gas connection between said chamber and the atmosphere.

7. A valve device for controlling the flow of gas between a source of gas under pressure and a tracheal passage and between the tracheal passage and the atmosphere comprising gas pressure conducting means, a gas chamber having an opening through which passes the gas flowing between said chamber and the tracheal passage, movable means subject to the gas pressure in said chamber and having a normal position and an actuated position, means for exerting on said movable means a force in opposition to the force exerted thereon by the gas pressure in said chamber so that said movable means moves from its normal position to its actuated position in response to the pressure in said cham ber exceeding a predetermined value above the atmospheric pressure, and means controlled by said movable means when in its normal position for establishing a gas connection between said gas pressure conducting means and said chamber and when in its actuated position for establishing a gas connection between said chamber and the atmosphere and for decreasing said opposing 'force to a predetermined value so that said movable means remains in its actuated posi tion until the gas pressure in said chamber decreases below a predetermined value above the atmospheric pressure.

8. A valve device for controlling the flow of gas between a source of gas under pressure and a tracheal passage and between the tracheal passage and the atmosphere comprising gas pressure conducting means, a gas chamber having an opening through which passes the gas flowing between said chamber and the tracheal passage, a diaphragm subject to the gas pres sure in said chamber and having a normal position and an actuated position, means for exerting on'said diaphragm a force in opposition to the force exerted thereon by the gas pressure in said chamber so that said diaphragm moves from its normal position to its actuated position in response to the pressure in said chamber exceeding a predetermined value above the atmospheric pressure, and means controlled by said diaphragm when in its normal position for establishing between said gas pressure conducting means and said chamber a gas'connection having a predetermined effective cross sectional area and when in its actuated position for establishing between said chamber and the atmosphere a gas connection having a smaller effective cross sectional area than said first mentioned gas connection and for decreasing said opposing force to 'a predetermined value so that said diaphragm remains in its actuated position until the gas pressure in said chamber decreases below a predetermined value above the atmospheric pressure. 9. A valve device for controlling the flow of gas between a source of gas under pressure and a tracheal passage and between the tracheal passage and the atmosphere comprising two gas chambers, one of said chambers having an opening through which passes the gas flowing between one'of said chambers and the tracheal passage, a movable member having a normal position and an actuated position, means responsive to the gas pressure in said one of said chambers for moving said member from said normal position to said actuated position, means responsive to the gas pressure in the other chamber for opposing the movement of said member from said normal position to said actuated position, said gas pressure responsive means and said member being so arranged that equal changes in the gas pressures in both chambers respectively produce difierent changes in the effects produced on said member by said gas pressure responsive means, and means controlled by said member for supplying gas under pressure to both of said chambers when said member is in its normal position and for shutting off the supply of gas under pressure to both of said chambers and for 'quickly' decreasing the gas pressure in said other chamber and for gradually decreasing the gas pressure in said one of said chambers when said member is in its actuated position.

10. A valve device for controlling the flow of gas between a source of gas under pressure and a tracheal passage and between the tracheal passage and the atmosphere comprising two gas chambers, one of said chambers having an opening 'through which passes the gas flowing between one of said chambers and the tracheal passage, a movable member having a normal position and an actuated position, means responsive to the gas pressure in said one of said chambers for moving said member from said i normal position to said actuated position, means responsive to gas pressure in the other chamber for opposing the movement of said member from said normal position to said actuated position. said gas pressure responsive means and said member being so arranged that equal changes" in the gas pressures in both chambers respectively produce difierent changes in the effects produced on said member by said gas pressure responsive means, adjustable means associated with said member for varying the gas pressure required in said chambers to effect movement of said member from said normal position to its actuated position, and means controlled by said I member for supplying gas under pressure to both of said chambers when said member is in its normal position and for shutting off the supply I of gas under pressure to both of said chambers and for quickly decreasing the gas pressure in said other chamber and for gradually decreasing the gas pressure in said one of said chambers when said member is in its actuated position,

11. A valve device for controlling the flow of gas between a source of gas under pressure and a tracheal passage and between the tracheal passage and the atmosphere comprising two gas chambers, one of said chambers having an opening through which passes the gas flowing between one of said chambers and the tracheal passage, a pivoted member having a normal position and an actuated position, means responsive to gas pressure above atmospheric pressure in said one of said chambers for rotating said member from said normal position to said actuated position, means responsive to gas pressure above atmospheric pressure in the other chamber for opposing the rotation of said member from said normal position to said actuated position, said gas pressure responsive means and said member being so arranged that simultane ous equal changes in the gas pressures in both chambers change the rotational efiect produced on said member by said first mentioned pressure responsive means a greater amount than the opposing rotational effect produced thereon by said second mentioned pressure responsive means, an adjustable spring tending to rotate said pivoted member toward its normal position, and means controlled by said member for supplying gas under pressure to both of said chambers when said member is in its normal position and for shutting off the supply of gas under pressure to both of said chambers and for quickly decreasing the gas pressure in said other chamber and for gradually decreasing the gas pressure in said one of said chambers when said member is in its actuated position.

12. A valve device for controlling the flowof gas between a source of gas under pressure and a tracheal passage and between the tracheal said one of said chambers for rotating said member from said normal position to said actuated position, means responsive to gas pressure above atmospheric pressure in the other chamber for opposing the rotation of said member from said normal position to said actuated position, and means controlled by said member for supplying gas under pressure to both of said chambers when said member is in its normal position and for shutting off the supply of gas under pressure to both of said chambers and for quickly decreasing the gas pressure in said other chamber and for gradually decreasing the gas pressure in said one of said chambers when said member is in its actuated position.

13. A valve device for controlling the flow of gas between a source of gas under pressure and a tracheal passage and between the tracheal passage and the atmosphere comprising a gas chamber having an opening through which passes the gas flowing between said chamber and the tracheal passage, means responsive to the gas pressure in said chamber for supplying gas under pressure to said chamber at a predetermined rate in response to the gas pressure in said chamber decreasing below a predetermined value above the atmospheric pressure and for exhausting the gas pressure in said chamber to the atmosphere at a lower rate in response to the gas pressure in said chamber exceeding a predetermined value above the atmospheric pressure, and means responsive to the gas pressure in said chamber decreasing to a predetermined value below said first mentioned predetermined value for increasing the rate at which the gas is supplied to said chamber.

14. A valve device for controlling the flow of gas between a source of gas under pressure and a tracheal passage and between the tracheal passage and the atmosphere comprising gas pressure conducting means, a gas chamber having an opening through which passes the gas flowing between said chamber and the tracheal passage, means responsive to the gas pressure in said chamber for establishing a gas connection of a predetermined eiTective cross sectional area between said chamber and said gas pressure conducting means in response to the gas pressure in said chamber decreasing below a predetermined value above the atmospheric pressure and for establishing a gas connection of a smaller effective cross sectional area between said chamber and the atmosphere in response to the gas pressure in said chamber exceeding a predetermined value above the atmospheric pressure, and means responsive to the pressure in said chamber decreasing to a predetermined value below said first mentioned predetermined value for increasing the effective area of the gas connection between said chamber and said gas pressure con ducting means.

15. A valve device for controlling the flow of gas between a source of gas under pressure and a tracheal passage and between the tracheal passage and the atmosphere comprising a gas chamber having an opening through which passes the gas flowing between said chamber and the tracheal passage, a movable member subject to the gas pressure in said chamber, means for exerting on said member a force in opposition to the force exerted by the gas pressure in said chamber, means controlled by said member for supplying gas under pressure to said chamber at a predetermined rate in response to the gas pressure in said chamber decreasing below a predetermined value above the atmospheric pressure and for exhausting the gas pressure in said chamber to the atmosphere in response to the gas pressure in said chamber exceeding a predetermined value above the atmospheric pressure, and means controlled by said movable member in response to the gas pressure in said chamber decreasing to a predetermined value below said first mentioned predetermined value for increasing the rate at which the gas under pressure is supplied to said chamber.

16. A valve device for controlling the flow of gas between a source of gas under pressure and a tracheal passage and between the tracheal passage and the atmosphere comprising gas pressure conducting means, a gas chamber having an opening through which passes the gas flowing between said chamber and the tracheal passage, a movable member subject to the gas pressure in said chamber, means for exerting on said member a force in opposition to the force exerted by the gas pressure in said chamber, means controlled by said member for establishing a gas connection between said gas pressure conducting means and said chamber in response to the gas pressure in said chamber decreasing below a predetermined value above the atmospheric pressure and for exhausting the gas pressure in said chamber to the atmosphere in response to the gas pressure in said chamber exceeding a predetermined value above the atmospheric pressure, another gas connection between said chamber and said gas pressure conducting means, a normally closed valve in said last mentioned gas connection, and means controlled by said movable member for opening said valve in response to the gas pressure in said chamber decreasing to a predetermined value below said first mentioned predetermined value.

17. A valve device for controlling the flow of gas between a source of gas under pressure and a tracheal passage and between the tracheal passage and the atmosphere comprising a gas chamber having an opening through which passes the gas flowing between said chamber and the tracheal passage, means responsive to the gas pressure in said chamber for supplying gas under pressure to said chamber at a predetermined rate in response to the gas pressure in said chamber decreasing below a predetermined value and for exhausting the gas pressure in said chamber to the atmosphere at a lower rate than said predetermined rate in response to the gas pressure in said chamber exceeding a predetermined value, and means for varying the rate at which the gas pressure in said chamber is exhausted to the atmosphere relatively to the rate at which the gas is supplied to said chamber.

18. A valve device for controlling both at high and low altitudes the flow of gas between a source of gas under pressure and a tracheal passage and between the tracheal passage and the atmosphere comprising a gas chamber having an opening through which passes the gas flowing between said chamber and the tracheal passage, means responsive to the gas pressure in said chamber for effecting an inhalation in response to the chamber gas pressure decreasing below a predetermined value and until the chamber pressure subsequently increases above a second predetermined value above said first mentioned value and for effecting an exhalation in response to the chamber pressure exceeding said second predetermined value and until the chamber pressure subsequently decreases below said first mentioned predetermined value, and means for preventing hyperventilation at high altitudes comprising means for varying the length of the exhalation period relative to the inhalation period.

asraoee 19. A valve device for controlling both at high and low altitudes the flow of gas between a source of gas under pressure and a tracheal passage and between the tracheal passage and the atmosphere comprising a gas chamber having an opening through which passes the gas flowing between said chamber and the tracheal passage, means responsive to the gas pressure in said chamber for supplying gas under pressure to said chamber in response to the chamber gas pressure decreasing below a predetermined value and for shutting oil the supply of gas under pressure and exhausting the gas pressure from said chamber to the atmosphere in response to the chamber gas pressure exceeding a predetermined value above said first mentioned value and until the chamber pressure decreases below said first mentioned value, and means for preventing hyperventilation at high altitudes comprising means for varying the rate at which the gas is exhausted from said gas chamber at such high altitudes.

20. A valve device for controlling both at high and low altitudes the flow of gas between a source of gas under pressure and a tracheal passage and between the tracheal passage and the atmosphere comprising a gas chamber having an opening through which passes the gas flowing between said chamber and the tracheal passage, means responsive to the gas pressure in said chamber for supplying gas under pressure to said chamber in response to the chamber gas pressure-decreasing below a predetermined value above the ambient atmospheric pressure and for shutting off the supply of gas under pressure to said chamber and exhausting the gas pressure from said chamber to the atmosphere in response to the chamber gas pressure exceeding a predetermined value above said first mentioned value and until the chamber pressure decreases below said first mentioned value, and means for preventing changes in the density of the gas due to changes in altitude from varying the rhythm of the apparatus comprising means for varying the effective cross sectional area of the passage through which the gas is exhausted from said chamber to the atmosphere.

21. A valve device for controlling both at high and low altitudes the flow of gas between a source of gas having a pressure which is maintained constant at a predetermined value above the ambient atmospheric pressure and a tracheal passage and between the tracheal passage and the ambient atmospheric pressure comprising gas pressure conducting means, a gas chamber having an opening through which passes the gas flowing between said chamber and the tracheal passage, means responsive to the gas pressure in said chamber for establishing a connection from said gas pressure conducting means to said chamber in response to the chamber gas pressure decreasing below a predetermined value above the ambient atmospheric pressure and for shutting off said connection from said gas pressure conducting means and for establishing a connection from said chamber to the atmosphere in response to the chamber pressure exceeding a predetermined value above said first mentioned value and until the chamber pressure decreases below said first mentioned value, and means for preventing hyperventilation at high altitudes comprising means for decreasing the effective cross sectional area of the connection established between the chamber and the atmosphere relatively to the efiective cross sectional area of the connection between the chamber and said gas pressure conducting means at such high altitudes.

22. A valve device for controlling the flow of gas between a source of gas under pressure and a tracheal passage and between the tracheal passage and the atmosphere comprising gas pressure conducting means, a gas chamber having an opening through which passes the gas flowing between said chamber and the tracheal passage, a plurality of gas passages connected to said chamber, means for establishing a gas connection between said plurality of gas passages and said gas pressure conducting means so that gas is supplied in parallel through said passages to said chamber, means responsive to the gas pressure in said chamber exceeding a predetermined value above the atmospheric pressure for shutting off said gas connection between said gas pressure conducting means and said plurality of gas passages and for establishing a gas connection between a portion of said plurality of gas passages and the atmosphere, means responsive to the gas pressure in said chamber decreasing below a predetermined value above the atmospheric pressure for shutting off said gas connection to the atmosphere and for reestablishing said gas connection between said plurality of gas passages and said gas pressure conducting means, and means for varying the efiective cross sectional area of that portion of said plurality of gas passages Which is arranged to be connected to atmosphere relatively to the effective cross sectional area of the remaining portion of said gas passages.

23. A valve device for controlling the flow of gas between a source of gas under pressure and a tracheal passage and between the tracheal passage and the atmosphere comprising gas pressure conducting means, a gas chamber having an opening through which passes the gas flowing between said chamber and the tracheal passage, two gas passages connected to said cham'- ber, means for establishing a gas connection between each of said gas passages and said gas pressure conducting means, means responsive to the gas pressure in said chamber exceeding a predetermined value above the atmospheric pressure for shutting off the gas connection between said two gas passages and said gas pressure conducting means and for establishing a gas connection between one of said gas passages and the atmosphere, means responsive to the gas pressure in said chamber decreasing below a predetermined value above the atmospheric pressure for shutting ofi said gas connection between said one of said gas passages and the atmosphere and for re-establishing said gas connection between both of said gas passages and said gas pressure conducting means, and means for varying the relative efiective cross sectional areas of said two gas passages while maintaining the effective total cross sectional area thereof constant.

24. A valve device for controlling the flow of gas between a source of gas under pressure and a tracheal passage and between the tracheal passage and the atmosphere comprising two gas chambers, one of said chambers having an opening through which passes the gas flowing between one of said chambers and the tracheal passage, a movable member having a normal position and an actuated position, means responsive to the gas pressure in said one of said chambers for moving said member from said normal position to said actuated position, means responsive to the gas pressure in the other chain her for opposing the movement of said member from said normal position to said actuated position, said gas pressure responsive means and said member being so arranged that equal changes in the gas pressures in both chambers respectively produce different changes in the effects produced on said member by said gas pressure responsive means, a gas passage interconnecting said chambers, other gas passages respectively connected to said chambers, means for varying the relative effective cross sectional areas of the two gas passages connected to said one of said chambers, and means controlled by said member for supplying gas under pressure to said other gas passages when said member is in its normal position and for shutting off the supply of gas under pressure to said other gas passages and for establishing a gas connection between the atmosphere and said other gas passage connected to said other chamber when said member is in its actuated position.

25. A valve device for controlling the flow of gas between a source of gas under pressure and a tracheal passage and between the tracheal passage and the atmosphere comprising two gas chambers, one of said chambers having an opening through which passes the gas flowing between one of said chambers and the tracheal passage, a movable member having a normal position and an actuated position, means responsive to the gas pressure in said one of said chambers for moving said member from said normal position to said actuated position, means responsive to the gas pressure in the other chamber for opposing the movement of said member from said normal position to said actuated position, said gas pressure responsive means and said member being so arranged that equal changes in the gas pressures in both chambers respectively produce different changes in the eifects produced on said member by said gas pressure responsive means, a gas passage interconnecting said chambers, other gas passages respectively connected to said chambers, adjustable means for simultaneously varying the relative effective cross sectional areas of the two gas passages connected to said one of said chambers while maintaining the efiective total cross sectional area thereof constant, and means controlled by said member for supplying gas under pressure to said other gas passages when said member is in its normal position and for shutting ofi the supply of gas under pressure to said other gas passages and for establishing a gas connection between the atmosphere and said other gas passage connected to said other chamber when said member is in its actuated position.

26. A valve device for controlling the flow of as between a source of gas under pressure and a tracheal passage and between the tracheal passage and the atmosphere comprising gas pressure conducting means, a gas chamber having an opening through which passes the gas flowing between said chamber and the tracheal passage, said opening being of sufiicient cross section not to prevent the pressure in said chamber from immediately following changes in the tracheal passage, a pressure responsive device responsive to the gas pressure in said chamber and having a movable member which moves quickly from one predetermined position to a second predetermined position in response to said gas pressure increasing above a predetermined value above the atmospheric pressure and which moves back quickly from said second predetermined position to said one predetermined position in response to said gas pressure decreasing below a predetermined value below said first mentioned value but above the atmospheric pressure, a two position valve device for establishing in one position thereof a gas connection between said gas pressure conducting means and said chamber and for establishing in the other position thereof a gas connection between said chamber and the atmosphere, and actuating means for said valve device selectively controlled by the position of said movable member.

27. A valve device for controlling the flow of gas between a source of gas under pressure and a tracheal passage and between the tracheal passage and the atmosphere comprising gas pressure conducting means, a gas chamber having an opening through which passes the gas flowing between said chamber and the tracheal passage, said opening being of suflicient cross section not to prevent the pressure in said chamber from immediately following changes in the tracheal passage, a pressure responsive device responsive to the gas pressure in said chamber and having a movable member which moves quickly from one predetermined position to a second predetermined position in response to said gas pressure increasing above a predetermined value above the atmospheric pressure and which moves back quickly from said second predetermined position to said one predetermined position in response to said gas pressure decreasing below a predetermined value below said first mentioned value but above the atmospheric pressure, a two position valve having an inhalation position in which a gas connection is established between said gas pressure conducting means and said chamber and an exhalation position in which a gas connection is established between said chamber and the atmosphere, a two position gas pressure operated device connected to said valve so that when said gas pressure operated device is in one of its positions said valve is in its inhalation position and when said gas pressure operated device is in its other position said valve is in its exhalation position, and means responsive to the position of said movable member for controlling the gas connection between said gas pressure conducting means and said gas pressure operated device to change the position of said gas pressure operated device.

28. A valve device for controlling the flow of gas between a source of gas under pressure and a tracheal passage and between the tracheal passage and the atmosphere comprising gas pressure conducting means, a gas chamber having an opening through which passes the gas flowing between said chamber and the tracheal passage, said opening being of suflicient cross section not to prevent the pressure in said chamber from immediately following changes in the tracheal passage, a pressure responsive device responsive to the gas pressure in said chamber and having a movable member which moves quickly from one predetermined position to a second predetermined position in response to said gas pressure increasing above a predetermined value above the atmospheric pressure and which moves back quickly from said second predetermined position to said one predetermined position in response to said gas pressure decreasing below a predetermined value below said first mentioned value but above the atmospheric pressure, a two position valve for establishing in one position thereof a gas connection between the aaiaoae atmosphere and said chamber and for establishing in the other position thereof a gas connection between said chamber and said gas pressure conducting means, an electromagnet for actuating said valve from said one position to said other position. and means controlled by said device for establishing an energizing circuit for said electromagnet while said movable member is in said one predetermined position.

29. A valve device for controlling the flow of gas between a source of gas under pressure and a tracheal passage and between the tracheal passage and the atmosphere comprising gas pressure conducting means, a gas chamber having an opening through which passes the gas flowing between said chamber and the tracheal passage, a movable member, means operated by the gas pressure in said chamber for moving said member from one predetermined position to a second predetermined position in response to the gas pressure in said chamber exceeding a predetermined value above the atmospheric pressure and from said second predetermined position to said one predetermined position in response to the gas pressure in said chamber decreasing below a second predetermined value above the atmospheric pressure and lower than said first mentioned predetermined value, a two position valve device establishing in one of its positions a gas connection between said chamber and said gas pressure conducting means and in its other position a gas connection between said chamber and the atmosphere, a gas operated device for operating said valve device including a second gas chamber, a second movable member subject to the gas pressure in said second gas chamber, and means controlled by said first mentioned movable member for controlling the gas pressure in said second gas chamber in accordance with the position of said first mentioned movable member.

30. A valve device for controlling the flow of gas between a source of gas under pressure and a tracheal passage and between the tracheal passage and the atmosphere comprising gas pressure conducting means, a gas chamber having an opening through which passes the gas flowing between said chamber and the tracheal passage, a movable member, means operated by the gas pressure in said chamber for moving said member from one predetermined position to a second predetermined position in response to the gas pressure in said chamber exceeding a predetermined value above the atmospheric pressure and from said second predetermined position to said one predetermined position in response to the gas pressure in said chamber decreasing below a second predetermined value above the atmospheric pressure and lower than said first mentioned predetermined value, a two position valve device establishing in one of its positions a gas connection between said chamber and said gas pressure conducting means and in its other position a gas connection between said chamber 28 and the atmosphere, a gas operated device for operating said valve device including a second gas chamber, a second movable member subject to the gas pressure in said second gas chamber, a restricted gas connection between said gas pressure conducting means and said second gas .chamber, a relatively large gas passage interconnecting said gas chambers, and means controlled by said first mentioned movable member for shutting 011 said relatively large gas passage while said first mentioned movable member is in said second predetermined position.

31. A valve device for controlling the flow of gas between a source of gas under pressure and a tracheal passage and between the tracheal passage and the atmosphere comprising two gas chambers, one of said chambers having an opening through which passes the gas flowing between one of said chambers and the tracheal passage, gas pressure conducting means, a movable member having a normal position and an actuated position, means responsive to the gas pressure in said one of said chambers for moving said member from said normal position to said actuated position, means responsive to the gas pressure in the other chamber for opposing the movement of said member from said normal position to said actuated position, said gas pressure responsive means and said member being so arranged that equal changes in gas pressures in both chambers respectively produce different changes in the effects produced on said member by said gas pressure responsive means, a gas connection between said chambers, a two position valve device establishing in one of its positions a gas connection between both of said chambers and said gas pressure conducting means and in its other position a gas connection between said other chamber and the atmosphere, a gas operated device for operating said valve device including a third gas chamber, a second movable member subject to the gas pressure in said third gas chamber, a restricted gas connection between said gas pressure conducting means and said third gas chamber, a relatively large gas passage connected to said third gas chamber, and means controlled by said first mentioned movable member for shutting off said relatively large gas passage when said first mentioned movable member is in said actuated position.

ARTHUR J. KIZAUR.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,121,311 Anderson et a1 June 21, 1938 2,138,845 Erickson Dec. 6, 1938 2,288 436 Cahan June 30, 1942 2,268,172 Sinnett Dec. 30, 1941 2,269,904 Erickson Jan. 13, 1942 2,310,189 Deming Feb. 2, 1943 

